The Catholic hierarchy has demanded that the country's MPs are given a free vote after the Irish government announced that votes would be whipped next year in a bid to get the controversial legislation through parliament.

"On a decision of such fundamental moral importance, every public representative is entitled to complete respect for the freedom of conscience," said a statement from the Catholic primate Cardinal Sean Brady and the archbishops of Dublin, Cashel and Tuam.

"The unavoidable choice that now faces all our public representatives is: will I choose to defend and vindicate the equal right to life of a mother and the child in her womb in all circumstances, or will I choose to licence the direct and intentional killing of the innocent baby in the womb?".

Leo O'Reilly, the bishop of Kilmore, attacked the legislation as the first step on the way "to a culture of death". "For the very first time in Ireland it would inevitably lead to the most liberal kind of abortion," he told the Irish RTE broadcaster.

To ensure the controversial law is passed the government whip will be applied to MPs in Ireland's ruling Fine Gael party which is deeply divided over the proposals.

Up to 20 Fine Gael MPs, including ministers, have raised their concerns in recent weeks about the inclusion in any legislation of the threat of suicide as a ground for abortion.

The Irish Times on Wednesday warned that the reforms, in the pipeline for 20 years, could challenge Irelandﾒs fragile ruling coalition between Fine Gael and the pro-abortion Labour Party.

"It has been evident for some time that this issue would present Fine Gael with a huge predicament. The focal point of contention surrounds the inclusion of the risk of suicide as a legal ground for abortion, which will severely test the party's cohesion," the newspaper noted.

Under current Irish law abortion is criminal unless it occurs as the result of a medical intervention performed to save the life of the mother.

The new legislation will drafted to comply with a landmark ruling in the European Court of Human Rights two years ago and a 1992 Irish Supreme Court decision in the "X case".

The Irish ruling 20 years ago overturned an injunction preventing a 14-year girl, who had been raped and was suicidal because she could not get a legal abortion, from travelling to Britain to have her pregnancy terminated.

She later had a miscarriage but her case did not lead to legal reform adding to confusion over when abortion was allowed in Ireland.